First, we compare the spectra of SNe 2010lp and 1991bg with synthetic spectra
obtained with the model that was used to match SN 1991bg. Fig.
REF  shows the spectrum of SN 2010lp obtained 264 days after
maximum [1]} and that of SN 1991bg obtained 203 days after maximum (corresponding to an epoch \(\approx 221\)  days after explosion), scaled down in flux to match the spectrum of SN 2010lp. Both spectra are shown in the rest frame and without a reddening correction. Two synthetic spectra are also shown: one is the model used for SN 1991bg [2]}, now computed at an epoch of 275 days, which should be a reasonable approximation for the epoch of the spectrum of SN 2010lp, and the other is a spectrum obtained using the same density structure and epoch but with an increased \(^{56}\) Ni mass (\(0.08\)  \(\textrm {M}_{\odot }\)  instead of \(0.06\)  \(\textrm {M}_{\odot }\) ), which yields a closer match to the observed flux of SN 2010lp (but not to its detailed features). The synthetic spectra are reddened with \(E(B-V)_{\rm tot} = 0.14\) , the reddening assumed for SN 2010lp. As expected, the synthetic spectrum reproduces some features of SN 2010lp, but shows a narrow [Fe iii] emission feature near 4700 Å, which is absent in SN 2010lp. The feature near 5200 Å contains [Fe ii] emission from the surrounding layers and is not completely suppressed even in SN 2010lp.
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